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This paper presents three case studies where aerobic effluent was utilized to recover failing onsite systems. The sites are described as follows: 1) a residential system with a gravity drainfield, 2) a residential system with a mound, and 3) a caf with a gravity drainfield. The paragraphs to follow summarize the methods employed when determining the cause of the failures. This report also demonstrates how the onsite systems can be recovered. As a comparative analysis the data associated with each case study is tabulated showing the design loading (Health Department Guidelines), the loading at failure, and the loading after recovery. The data includes Flow, L/d (gpd), (Flows per square meter and foot), BOD5, TPPD of BOD5, (Total pounds per day per square meter and foot), TSS, (Total Suspended Solids), FOG, (Fats, Oils, Grease), pH, Temperature, and DO, (Dissolved Oxygen). One Aerobic Treatment Unit (ATU) product line was selected for the study, which consisted of a residential model and a commercial model. Both models maintained similar features including; 1) control of system flow, 2) the reduction BOD5 by a percentage, 3), the discharge of a very high DO with an pH near seven, and 4), and discharge aerobic microorganisms.